Movement detector for composite color television signals

• US 4,811,092 A
• Filed: 08/14/1987
• Issued: 03/07/1989
• Est. Priority Date: 09/12/1986
• Status: Expired due to Term

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Saito, Shobu, Ishikura, Kazuo, Katsumata, Kenji, Sugiyama, Masato, Achiha, Masahiko
• Primary Examiner(s): Britton, Howard W.
• Assistant Examiner(s): Kostak, Victor R.
• Application Number:
  US07/085,894
• Time in Patent Office: 571 Days
• Field of Search: 358/105, 358/136, 358/31, 358/21 R
• US Class Current: 348/702
• CPC Class Codes: G06T 7/254 involving subtraction of images
• CPC Class Codes: H04N 5/144 Movement detection for video coding H04N19/503; analysis of motion in general G06T7/20

Abstract

A movement detector necessary for processing composite color television signals, which detects movement in image signals, wherein the detecting circuit is so constructed that no deficient motion is produced. A difference signal between the present frame and that preceding by two frames of the television signals is converted into a motion information signal and a movement detection signal is made by integrating the signal obtained by the conversion with respect to temporal axis.

Claims

1. A movement detector in NTSE composite color television signals comprising:

a frame memory for delaying television signals by two frame periods;

a subtractor for obtaining the difference between the input and the output signals of said frame memory;

a motion information converting circuit for obtaining motion information from the output signal of said subtractor; and

a temporally integrating circuit for integrating the output signal of said motion information converting circuit with respect to temporal axis to obtain a movement detection output signal.

2. A movement detector in composite color television signals according to claim 1, wherein said motion information converting circuit is constituted by an absolute circuit for forming the absolute value of the output signal of said subtractor, a low pass filter, in which the output of said absolute circuit is inputted, and a first ROM addressing the output of said low pass filter, and said integrating circuit includes a field memory and a line memory connected in series, an averaging circuit for forming the average of the input and the output of the line memory, and an adder, which adds said average value to the output of said motion information converting circuit and applies a part of the sum thus obtained to said field memory, the other part thereof being the movement detection signal.

3. A movement detector in composite color television signals according to claim 2, further comprising:

a circuit for obtaining a difference signal between adjacent frames of said television signals;

a circuit for obtaining the low frequency component of said difference signal between adjacent frames;

a second ROM for converting magnitude of said low frequency component into motion information; and

a circuit for combining the output of said second ROM to the output of said first ROM.

4. A movement detector in composite color television signals comprising:

a first circuit for obtaining first motion information from the low frequency component of a difference signal between adjacent frames for the luminance signal of an inputted television signal;

a second circuit for demodulating a color signal of the inputted television signal;

a third circuit for obtaining a difference signal between the present frame and that preceding by two frames for the output of said second circuit;

a fourth circuit for obtaining second motion information from the output of said third circuit;

a fifth circuit for combining said first and said second motion information; and

an integrating circuit for integrating the output of said fifth circuit to make a part of the value thus obtained the motion detection signal.